Docusate is the generic name of a surfactant used as a stool softener, which is sold under multiple brand names, for example AQUALAX ®, CALUBE ®, and COLACE ®. Docusate is administered to make stools softer and easier to pass. It is used to treat constipation due to hard stools, in painful anorectal conditions such as hemorrhoids, and for people who should avoid straining during bowel movements. Unfortunately, docusate possesses a strong, unpleasant and bitter taste.
The disagreeable taste of compounds such as docusate is generally not of concern when formulating oral solid dosage forms, because the compound's taste can be easily masked with an exterior coating. The orally administered drug can be provided to the patient in many dosage forms, including solid forms such as capsules, caplets or tablets. Pharmaceutically active agents administered in solid dosage form are usually intended to be swallowed whole.
Many patients, including children, the elderly, and disabled or incapacitated patients, often have trouble swallowing tablets or capsules. In these situations, it is desirable to provide the drug either in a chewable solid form or in a liquid form, such as a solution, syrup, emulsion or suspension. For many patients, a liquid oral dosage form is preferred over a chewable dosage form because of the ease with which a liquid may be swallowed. Additionally, patients may be more inclined to comply with their medication instruction if the dosages are easier to ingest.
Liquid pharmaceutical compositions that include an unpleasant tasting pharmaceutically active agent, such as docusate, usually require the taste to be obscured. Accordingly, a common formulation challenge associated with liquid dosage forms is masking the disagreeable taste of the active ingredient. Unfortunately, commercially available liquid formulations of docusate do not satisfactorily mask its taste, giving rise to difficulties in administration and in assuring patient compliance. Thus, it is desirable to provide a docusate liquid formulation that better masks its taste than those currently available.